send data from browser instance to wetty iframe

[sanjeethboddi]

I want to send a data like keys/passwords/random_string from browser to the wetty iframe and write it to terminal when logs in.
I've tried to postMessage to iFrame but not sure how the iframe will receive it.

reference: https://stackoverflow.com/questions/9153445/how-to-communicate-between-iframe-and-the-parent-site